Improvement in air-brakes for railroad-cars



. 4 Sheet s-Sheet 1. R. SGHULTZ, called NIBURN.

Air-Brake for Railroad-Cars.

NQ. 220,178. Patented-sept. 3o, 1879.

" "y 4 aziz( N.PETERS. PHOTO-LITHOGRAPb-IERA WASHINGTON, D C.

' Lsheets--Sheet 2. R.,SCHULTZ, called NIBORN.

Air-Brake fqr Railroad-Gars.

Patented Sept. 3o, 1879.

N.PETEHS, PHOTG-LITHDGRPNEFL WASHINGTON D C 4 Sheet S-Sheet 4.

R. SGHULTZ, called NIBORN.4 Air-Brake for Railroad-Gars.

No. 220,178. Patented Sept. 3o, 1879.

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r1A PETERS. PHuImLITHOGRAPHER. WASHINGTON. D G4 'UNITED STATES PATENT@TurionA- I ROBERT SCHULTZ, CALLED NIBORN, OF KATTOWITZ, PRUSSIA,GERMANY.

IMPROVEMENT IN AIR-BRAKES FOR RAILROAD-CARS.

Specilication forming part of Letters Patent No. 220,178. datedSeptember 30, 1879; application filed April 29, 1879.

To all whom it may concern.-

ejt known that I, ROBERT ScHUL'rz, called NIBORN, of the city ofKattowitz, Prussia, in the Empire of Germany, have invented an ImprovedAutomatic AinBrake for Railroad- Uars, of which the following is aspecication.

The main objection to the various automatic systems for braking bycompressed air, steam, or other agents was made against the centralsource of power in the same, by which the brakes of all the cars of atrain were controlled, and which rendered a durable and reliableconnection difficult and expensive, and for long trains the control ofthe rear part of the train uncertain and unreliable. Besides, anexpensive system of coupling for the communicating pipes is required,which makes, to some extent, the making up of trains, 8mo., lessconvenient.

The object of my invention is .to provide each car with a separateautomatically-working brake mechanism, in which compressed air visemployed as the actuating` agent, and by which each car of a train isrendered independ- 'ent of a central source of power. The brakes arethrown automatically into action in case an accident occurs at any partof the train, while also a signaling arrangement may be worked inconnectionl with the compressed-air reservoir, so that a higher degreeof safety for the passengers and the independence of each car in makingup the train are obtained.

The invention consists, essentially, ot' an air-pump, whose piston isworked by an eccentric on one of the truck-axles. The air-pump isconnected with a reservoir and a regulator, for discontinuingautomatically the working of the pump when a certain air-pressure isreached. A slide-valve of the compressed-air reservoir is connected withthe coupling and witha brake-cylinder, so as to apply the brakesautomatically to the car-wheels as soon as the strain on thecar-coupling is released, either by a decrease of speed, or on adescending gradient, or by an accident to any part of the train.

Referring to the drawings, Figure l represents a sectional sideelevation of a railroad ear, with my improved automatic-brake ar- 1rangement shown in vertical longitudinal section. Fig. 2 is a bottomView of the car and brake, partly in horizontal section. Fig. 3 is avertical axial section of the air-pump with its regulator and actuatingmechanism; Fig. 4, a horizontal section of the air-pump and regulator;Fig. 5, a vertical longitudinal section through air-pump, reservoir, andactuating mechanism; Fig. 6, a vertical transverse section of thecompressed-air reservoir and slidevalve; and Fig. 7 is a top View ot'the actuating-eccentric of the car-axle, drawn on an enlarged scale.

Similar letters of reference indicate corresponding parts.

To the bottom ofthe car-frame are attached, vertically above one of thetruck-axles, an airpump, A, and a reservoir, S, for the compressed air.The piston B of the air-pump is operated by means of an eccentric, E, ofcast-iron or oak, which is rigidly keyed to the axle. The greatestlength of the eccentric, is somewhat (about thirty millimeters) shorterthan the maximum stroke of the piston of the airpump. To both sides ofthe eccentric E are applied metal disks e, which are of somewhat largerdiameter than the eccentric, and provided with inwardly-projectin gannular flanges or keepers g, and with inwardlyinclined eircumferentialrails l. A space of about twentyiive millimeters in width is leftbetween the eccentric and the keepers of the side disks. These flangesor keepers are recessed at the points of maximum or minimum distancefrom the axle, as shown in Figs. 4 and 7, the width ot' these lateralrecesses being about fifty millimeters.

The inner faces of the flanges are at such distance from each other thatthe piston-rod, which is somewhat reduced 1n thickness at the lower end,passes readily through the open space between the flanges.

The lower end ofthe piston-rod is arranged with a cross-head, n n, whichfits by its convex under side into a circumferential center groove ofthe eccentric, and is engaged at both sides by the flan ges.

The ends of the cross-head are semicircular, so as to slide readilyalong the flanges, which are curved somewhat at their inner sides.

The cross-headisinserted betweenthetlanges by means of one of therecesses, and thereby the piston moved up and down by the eccentric assoon as the car is set in motion.

Air is drawn into the air-pump through a 'by diagonal channels c and dwith the lower and upper parts of the air-pump and by an exterior pipe,f, which extends from the top ofthe regulator to the bottom of theair-pump. Pipe f is closed by a spring-valve at its upper end in such amanner that air can pass into the regulating-chamber from the pump, butnot in opposite direction from the regulator to the ump.

The weighted slide-valve K closes, when in its lowermost position, thechannel e, but leaves the upper channel, d, open, so that the upper partof the air-pump communicates with the upper part of the regulator. Assoon as such a quantity of air is compressed in the reservoir S that thepressure of the same overcomes the weight ot' the slide-valve K of theregulator and its friction therewith, the slidevalve K will be raised,and thereby the upper channel, d, closed. The body of air which is thenyinclosed in the upper part of the regulator forms an air-cushion, thecompression of which produces a gradually-increasing resistance to theupward motion ot' the piston.

By the gradual increase ot' the air-pressure in the reservoir S and inthe space below the weighted slide-valve K the latter will be graduallyraised to such a height that the lower channel,c, will be opened. (Thisposition ot' the piston is indicated in dotted lilies in Fig. 3.) Thehighly-compressed air enters then into the air-pump below the piston.and forces the same in upward direction, which is furthermore assistedby the escape of the air above the piston, asin the same moment when thelower channel is opened the upper channel, d, is connected by a siderecess of the slide-valve K with an exit-channel, m, that communicateswith the atmosphere.

The pressure on the lower part of the piston of the air-pump sustainsthe piston in the upper part of the pump, and causes the disconnectionof the cross-head of the piston-rod from the keepers of the eccentric assoon as the cross-head arrives at one of the lateral recesses of theilanges. The pressure of the compressed air inthe reservoir retains thusthe piston B in the uppermost position, (shown in dotted lilies in Fig.4,) and keeps thereby the cross-head clear ot' the greatest eccentricityof the anges, so that they are prevented from engaging the cross-head.The air-pump is thus placed out of action for a time; but as soon as bythe decreasing pressure in the reservoir S the weighted slide-valve inthe regulating-chamber R slides downward again it will close the lowerchannel, c. The highly-compressed air below the piston of the air-pumpis then forced through the pipe ff, and acts with a considerable butgraduallydecreasing pressure on the weighted slidevalve until the samearrives again in its lowermost position, so as to open the upperchannel, d. The air can then pass from the upper part of the regulatorto the upper part of the air-pump, above the piston, and will force thesame down, so that the cross-head will drop on the tlan ges and slidealong the same until it can drop through the recesses into the annularspace below the same. The air-pump is thereby in perfectly automatiealmanner set into operation agaiu,faud serves to charge the reservoiruntil the pressure therein is capable of raising again the weightedslide-valve, so as to interrupt the functioning of the air-pump, and soon alternately.

To secure the vertical motion of the piston ot' the air-pump, thepiston-rod may be arranged with addltional side guide devices, while inpractice it may he advisable, for securing the proper working of thepump, to place the stuing-box of the pump as far as possible toward theinside of the pump, and eventually to incluse the entire pump by a.sheet-metal casing, so as to protect the same as much as possibleagainst dust.

As long as the car is in motion a constant air-pressure will be obtainedby the action of the air-pump, the pressure being regulated by a properconstruction and weight of the regulating slide-valve.

The compressed air which is thus obtained for each car by the mechanismdescribed may be utilized as a motive power for the purpose of actuatingthe brakes, as well as for signaling purposes. For the latter purpose apipe, p, leads from the reservoir S upward to a point above the root' ofthe car, and is there arranged with a whistle, s, in the nature of asteamwhistle. The escape ofthe compressed air is prevented by a doublelever-valve, g, and the latter opened by a lever-arm, h, which isconnected with a cord, z, that passes inside or outside of the car,according to the construction of the same.

By a prearranged system of signals the conductor, brakemen, orpassengers may in each car communicate with the engineer, so as to guardagainst accidents and furnish a complete control over all the cars ofthe train.

For employing the compressed air of the reservoir for the brakes, asmall brake-cylinder, G, is arranged intermediately between the truckaxles. The piston-rod of this cylinder is extended in both directions,and pivoted to the levers u of the brake-shoes c, which are applied tothe wheels or removed therefrom,

according as the compressed air acts on one.

side or the other of the piston. The supply of air to the brake-cylindermay be governed by a common slide-valve that is arranged in avalve-casing, D, below the reservoir S, the casing being connected bypipes t and il, re-

spectively, with the front and back of the brake-cylinder. Theslide-valve may be readily controlled by the brakeman by means of acommon elbow-lever, and thus the brakes be applied easily and quicklywith full force.

As by this method, however, but a comparatively small advantage over theold method of braking the cars would be obtained, it is preferable touse a slide-valve construction, by which the brakes are controlled bypurely mechanical means in an entirely automatical manner. This may beobtained by .connecting the guide-rod of the slide-valve by a rigidforked rod or link with a pivot-pin, 7c, of the coupling-link y, so thatas long as the couplinglink is kept by the strain in horizontal positionthe slide-valve is held in its foremost position, the slide-valve beingthereby drawn avay from the wheels.

As soon as, however, the cars are crowded up against each other, owingto a descending gradient in the track, or to a sudden braking of thelocomotive, or to the throwing of a car from'the track, the position ofthe couplinglink is changed from its horizontal position,

describing an arc of a circle, and pushing the slide-valve back. Thisadmits the compressed air to the other side of the piston of thebrakecylinder and applies the brakes,removing the -same again as soon asthe coupling-link is drawn up into a horizontal position again.

As the main object of this construction is to `apply the brakes as soonas the strain of the coupling is but slightly released, it is preferablefor overcoming any frictional resistance in the distribution of the airto employ not a common slide-valve, but a piston-valve, D', of theconstruction shown in Fig. 5. This piston-valve remains in the positionshown as long as the train is in motion, and as long as thecoupling-link and the guide-rod are drawn taut. In this position thepipe i2, which leads to the part back of the brake-piston, is placed incommunication by arecess of the piston-valve with the atmospheric air,while the compressed air acts not alone on the front face of thepistonvalve D; but also by achannel, d, of the same, and the pipe z", onthe front of the brake-piston, so as to keep thereby the brakes bydirect pressure away from the wheels. The pressure of the compressed airon both sides ot' the piston-valve balances the same, though there is atendency to push the piston-valve back. The piston-valve, however,cannot follow the air-pressure on its front face until thecoupling-link, for some reasons or other, is dropped from its horizontalposition, and allows thereby the backward motion ot' the piston-valve.The piston-valve places then the pipe il in communication with theatmospheric air and admits the passage of the compressed air to thebrake-cylinder, so as to instantly apply the brakes. This constructiondoes not require the rigid connection between guiderod andcoupling-link, but admits a iiexible connection by a chain, as shown inFig. 1, which is superior to the rigid rod, as by the breaking of thecoupling, for instance, in that case the slide-valve had to be made of alength corresponding to that of the coupling-link y. By the autoinaticalfunctioning of the piston-valve, in connection with the automaticworking ot' the air-pump and reservoir, it is possible to apply thebrakes in a more reliable and powerful manner than heretofore.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. The combination otl an air-pump, compressed-airreservoir, and pressure-regulating mechanism'with an actuating mechanismof the car-axle that is adapted to throw the airpump out of action whena maximum pressure is obtained in the reservoir, substantially as setfort-h.

2. The combination of an air-pump having a piston-rod and a cross-headat its lower end with a fixed eccentric of the truck-axle, arrangedvertically below the air-pump, the eccentric having side disks, withannular iianges or keepers, that engage the cross-head of thepiston-rod, substantially as and for the purpose specified.

3. An air-pump having a piston-rod and a cross-head, convex at the underside, in combination with an eccentric that is keyed to the truck-axlevertically below the air-pump, the eccentric having a centralguide-groove and side disks, with annular flanges and circumferentialinwardly-inclined rails, for retaining and guiding the cross-head,substantially as specified.

4. The combination of an air-pump having a piston-rod and a cross-headat its lower end with an eccentric of the truck-axle that is4 providedwith side disks, having iianges or keepers that are laterally recessedat one or more points, to admit the entrance or escape of the cross-headof the piston, substantially as and for the purpose set forth.

5. The combination of an air-pump with a reservoir for the compressedair, and with a regulator and weighted slide-valve, arranged sidewise ofthe air-pump, the regulator being connected to the air-pump andreservoir in such a manner that the functioning of the airpump isinterrupted when the maximum pressure is reached, substantially asdescribed.

6. The combination of the air-pump and reservoir S and regulatorR,having a weighted slide-valve, K, the air-pump and regulator havingcommunicating channels c d, valved communicating pipe f, and anexit-aperture, m, substantially as set forth.

7. The combination, with an air-pump operated intermittently byactuating mechanism of the car-axle, of a compressed-air reservoir, ot'an automatically-working pressure-regulator between air-pump andreservoir, of a slidevalve connected with the air-reservoir, and of abrake-actuating mechanism connected -with the slide-valve, so as toapply or remove the brakes by working the slide-valve, substantially asspecified.

8. The combination of the compressed-air reservoir, having aslide-valve, connected to the car-coupling, with a brakecylinder,piston, and brakes, so as to upplY the brakes automatically when thestrain on the couplingis relaxed, and remore them when the coupling isdrawn taut, substantially as set forth.

9. The combination of a compressed air reservoir, having a balancedpiston-vulve, that is connected to thel car-coupling, with abrakecylinder, piston, and brakes, and with pipes that connect the frontand buck ot' the pistonvalve casing, respectively, with the back andfront of the brake-cylinder, to automatically apply or remove the brakeson the relaxing or restoring the strain on the coupling, substantiallyas and for the purpose specited.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ROBERT SUHULTZ, CALLED N IBORN.

Witnesses HERMANN GoPEL, FRIEDRICH GORKE.

